The present invention relates to a refuse compactor in general, that is a compactor for compressing bulky substances and materials, especially household refuse such as kitchen waste, empty containers, cans, bottles and the like.
Refuse compactors of this general type are already commercially available. One of these has a frame, a container in the frame, and a parallellogram drive which moves a platen into the container in order to compress material located therein. The parallellogram drive has two pair of levers which are closely adjacent in vertical planes and pivotable about common axis. One end of each lever is mounted on a shiftable carriage and the other end of the levers are mounted at different sides of a bolt which is mounted in the center of the circular platen, extending axially of the latter. Because of the small lateral spacing between the levers, their relatively large length and because of the disadvantageous central force transmission by the levers upon the platen, the parallellogram drive of this known construction is not very resistant to flexing and bending. It is therefore particularly susceptible to reaction forces which act non-symmetrically and eccentrically upon the pressure platen and which develop when the platen compacts material in the container which is of differential composition, for example if at one side of the container the material is softer than at the other side. For this reason this known construction is not suitable for compacting of material which includes relatively large components, such as bottles, cans and the like and which when compressed will produce reaction forces which vary substantially in magnitude and which may suddenly and uncontrollably shift from one location of the platen to another. Since these reaction forces act only very rarely centrically and symmetrically upon the platen, they cause strong tilting moments to act upon the platen which are transmitted to the parallellogram drive and tend to flex or deform the same. This, in turn, causes substantial bearing friction in the journals of the drive, and these may lead either to a blockage of the drive or at the very least result in early destruction of the journals.
These problems could potentially be overcome in this prior-art construction by significantly increasing the strength of the individual components of the entire device. However, this is not practical because it would so increase the expense of the device that it would no longer be economically feasible to produce the device; moreover, it is desired that such devices be relatively light in weight in order to make them readily transportable since they are primarily intended for household use, and such increase in the strength of the components would result in an undesirable increase in the weight of the device.
Another prior-art device of the type in question uses an approximately rectangular pressure platen and the levers of the parallelogram drive are pivoted to the corners of the platen, being spaced from one another in lateral direction to a significantly greater degree than in the first-mentioned device. However, if reaction forces act upon the pressure platen in this device, it also tends to a deformation or flexing of the levers of the parallellogram drive, bringing with it the same disadvantages which have already been outlined above. In addition, if the reaction forces are strongly asymmetrical and eccentric with reference to the pressure platen, the latter tends to be shifted laterally to an extend sufficient for it to engage the container and to damage the latter during its further motions. In certain circumstances it is also possible for the platen to become completely blocked against further movement in the container.